Compound components in React
React interview exercise on Patterns, difficulty 3 of 3. Solve it in the editor beside a worked example, or cold in Interview mode with the example hidden; the tests run the moment you do.
Write Tabs({ defaultTab, children }) with Tabs.List (a <div role="tablist">), Tabs.Tab({ id, children }) (a <button role="tab" aria-selected> selecting its id on click) and Tabs.Panel({ id, children }) (a <div role="tabpanel">, rendered only for the selected id). The selected id lives in Tabs and is shared through context.
Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Interview mode hides the example: solve it from memory, without the hint or the solution, and it counts as solved cold. Progress is saved in your browser, and in your account if you sign in.